Alloy and apparatus made therefrom



Patented Sept-30, 1924.

warren s'raras ALADAR PACZ, 0F CLEVELAND HEIGHTS, OHIO.

ALLOY .A 1\TI) APPARATUS MADE THEREFROM.

No Drawing.

To all whom it may concern:

Be it known that I, ALADAR PAoz, a citizen of the United States, residing at Cleveland Heights in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Alloys and Apparatus Made Therefrom, of which the following is a full, clear, and exact description.

This invention relates to metallic alloys and has for its purpose the provision of a composition of great hardness, moderate heat expansion and good casting qualities for commercial uses. Certain of the-properties'of my improved alloy vary according to the proportions of certain ingredients, these properties merging into each other gradually. In its upper range, the material has a great many properties of cast iron, namely, easy casting, ready machining, absence of ductility or warping, and a high degree of elasticity. In this range, it is particularly useful for the parts of internal combustion or other engines, especially cylinders and piston rings. In its lower range which is characterized by a certain degree of ductility it constitutes a valuable composition for bearings and other devices for which bronzes of tin and aluminum have heretofore been used, thus overcoming on the one hand the expense of tin and on the other hand the difficulty of casting the aluminum bronze. In both ranges the alloy is non-corrodible, non-ca-rbonizing, and easily lubricated.

My improved composition consists essentially of the ternary alloy of copper, aluminum, and silicon. Copper is at all times present to an amount of at least 87% and is preferably maintained below 97% because of the increasing softness of the material above that point. It is preferable to keep the silicon content less than that of the aluminum, although if the total amount of silicon is less than about 4% of the whole,

' a useful alloy can be produced having a content of aluminum less than that of silicon. For example: Copper 97, silicon 2, aluminum 1, constitutes a rather soft, useful alloy;

copper. 96, silicon 3, aluminum 1 is noticeably harder but liable to a tendency towards harshness; copper 95, silicon 3, aluminum 2 forms a good bearing alloy; copper 93, silicon 4, aluminum 3 produces an alloy having very little ductility but good casting properties. p

Application filed June 1,

1920. Serial 1V0. 385,597.

By maintaining the proportion of the silicon less than that of the aluminum it is possible to decrease the amount of copper yet more, for example: Copper 93, silicon 3, aluminum 4 producesa strong, ductile alloy for good bearings. etc.; copper 92, silicon 3,

aluminum 5 produces a similar alloy of greater hardness; copper 91, silicon 3,

produce a most excellent, non-warping, re-

silient alloy.

1- am aware that the alloy of copper 89, aluminum 11 makes a bronze which possesses Very poor casting qualities and almost devoid of elasticity. A ring or other resilient shape, when dropped upon the floor, collapses much the same as lead but the substitution of a small quantity of silicon for some of the aluminum affords to the alloy an elasticity comparable'with that of hardened steel.

The limits of copper in my alloy are between about 87% and 97%; the limits of silicon are between about 2% and about 5% the limits of aluminum are between about 1% and about 10%. I do not here consider the efiect of fourth metals, impurities, etc.; except to point out that metals having an atomic weight between 50 and possess a very pronounced hardening-effect and hence should ordinarily be excluded excepting where this property is peculiarly desired.

The use of this material for bearings requires no particular description; in general the alloys containing upwards of 90% of copper are fitted for this use. The hardened and non-Warping varieties containing less than 90% of copper are peculiarly useful for the cylinders of internal combustion engines. Inasmuch as the material has a scleroscope hardness of 50 as compared with about 30 for cast iron, it is practically immune to wear; for some unknown reason carbon deposits in such a cylinder are almost unknown; the weight is no greater than that of cast iron; the coeflicient of heat expansion is somewhat greater than cast iron being about midway between iron and aluminum in this regard. Accordingly, when used as a sleeve inside a cast aluminum water jacket, there is much less tendency towards separation between the jacket and sleeve than if a steel sleeve is employed; and whether the cylinder be water cooled or air cooled (but especially on the air cooled type) it is possible to fit an aluminum piston with a smaller clearance than in the case of a cast iron cylinder owing to the fact that the cylinder will expand more nearly at the same rate with the piston. The ready casting qualities of the alloy also enable a water jacket to be cast therein, the same as with cast iron. In all cases the higher heat conductivity of the metal maintains the oil film at a lower-temperature than in case cast iron be employed and thus reduces friction, decreases carbonization, minimizes gas leakage, and increase engine power.

My improved alloy in its non-warping range also forms a most excellent composition for pistonrings, either in connection with iron cylinders or those of the same material. Another advantage of my alloy is that it isvery nearly immune to oxidation caused by prolonged heating in an oxidizing atmosphere. Its melting point is slightly below that of cast iron.

No special precautions are required in the production or manipulation of the alloy. Electricity, gas or coal can beused as desired, and a furnace either of the hearth type or crucible type can be employed though I prefer the latter in small scale work. Preferably the aluminum and silicon are, first alloyed together in, any suitable manner, and the mixture added to a bath of molten copper. 5 I

Another very important use for my improved alloy is in the manufacture of rubber molds, such forexample as those used for curing vehicle tires. The heat conductivity enables a certain saving in the time of curing, while the polished and incorrodible nature of the alloy avoids rusting and adhesion of the rubber and the ease of castin enables direct production of intricate tread forms, Many other uses will occur to those skilled in the art, and I claim. and secure my improved alloy, not only for .the particular uses mentioned, but also for all others to which it may be applicable, limiting myself in nowise, either use or composition, except as specifically recited in the claims hereto annexed.

Having thus described my invention, what I claim is: I

1. A metallic alloy for the purpose described, consisting essentially of copper at least 87%, silicon between 2% and 5% and at least 1% of aluminum.

2. A metallic alloy for the purpose de scribed, consisting essentially of copper at least 87%, silicon between 2% and 5% and an amount of aluminum greater than the amount of silicon.

3. A metallic alloy for the-purpose described, containing at least about 87% of copper together with silicon and aluminum, there being at least about 2% of silicon present, and the aluminum content being in excess of the silicon.

4. A metallic alloy for the purpose described, containing essentially between 87% and 90% of copper, from 2 to 3% of silicon, and the balance aluminum.

5. A non-warping, readily cast, non-corrodible, machinable alloy consisting essentially of from 87% to 90% of copper alloyed with silicon and aluminum, the aluminum constituting from 2 to 4K times that of the silicon.

6. A non-warping alloy of silicon, aluminum, and copper for engine parts, there being at least about 2% and not over about 5% of silicon, and between about 87% and 97% of copper, the balance being mostly aluminum.

7. Apparatus for heat exchange made from a non-corrodible, machinable alloy consisting essentially of from 87% to 97% of copper alloyed with from 1% to 3% of silicon, and at least 1% of aluminum.

8. A hollow, cylindrical body forming an element of a thermodynamic engine which is made of an alloy containing copper, silicon and aluminum, the copper being present in the amount of between 87% and 97%, the amount of aluminum being not materially less than that of silicon and silicon being present to at least 1%.

9. A cylinder of an internal combustion engine formed from an alloy containing copper in the amount of from 87 to 90%, silicon, and aluminum in the amount of from two to four times the amount of the silicon and not less than 2% of the whole.

In testimony whereof, I hereunto aflix my signature.

ALADAR PACZ. 

